﻿// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)'

// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)'


Shader "UI/UIBlur" {
	Properties{
			_Color("Main Color", Color) = (1,1,1,1)
			_BumpAmt("Distortion", Range(0,128)) = 10
			_MainTex("Tint Color (RGB)", 2D) = "white" {}
			_BumpMap("Normalmap", 2D) = "bump" {}
			_Size("Size", Range(0, 20)) = 1
	}

		Category{

				// We must be transparent, so other objects are drawn before this one.
				Tags { "Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Opaque" }


				SubShader {

				// Horizontal blur
				GrabPass {
					Tags { "LightMode" = "Always" }
				}
				Pass {
					Tags { "LightMode" = "Always" }

					CGPROGRAM
					#pragma vertex vert
					#pragma fragment frag
					#pragma fragmentoption ARB_precision_hint_fastest
					#include "UnityCG.cginc"

					struct appdata_t {
						float4 vertex : POSITION;
						float2 texcoord: TEXCOORD0;
					};

					struct v2f {
						float4 vertex : POSITION;
						float4 uvgrab : TEXCOORD0;
					};

					v2f vert(appdata_t v) {
						v2f o;
						o.vertex = UnityObjectToClipPos(v.vertex);
						#if UNITY_UV_STARTS_AT_TOP
						float scale = -1.0;
						#else
						float scale = 1.0;
						#endif
						o.uvgrab.xy = (float2(o.vertex.x, o.vertex.y*scale) + o.vertex.w) * 0.5;
						o.uvgrab.zw = o.vertex.zw;
						return o;
					}

					sampler2D _GrabTexture;
					float4 _GrabTexture_TexelSize;
					float _Size;

					half4 frag(v2f i) : COLOR {
						//                  half4 col = tex2Dproj( _GrabTexture, UNITY_PROJ_COORD(i.uvgrab));
						//                  return col;

											half4 sum = half4(0,0,0,0);
											#define GRABPIXEL(weight,kernelx) tex2Dproj( _GrabTexture, UNITY_PROJ_COORD(float4(i.uvgrab.x + _GrabTexture_TexelSize.x * kernelx*_Size, i.uvgrab.y, i.uvgrab.z, i.uvgrab.w))) * weight
											sum += GRABPIXEL(0.05, -4.0);
											sum += GRABPIXEL(0.09, -3.0);
											sum += GRABPIXEL(0.12, -2.0);
											sum += GRABPIXEL(0.15, -1.0);
											sum += GRABPIXEL(0.18,  0.0);
											sum += GRABPIXEL(0.15, +1.0);
											sum += GRABPIXEL(0.12, +2.0);
											sum += GRABPIXEL(0.09, +3.0);
											sum += GRABPIXEL(0.05, +4.0);

											return sum;
										}
										ENDCG
									}
				// Vertical blur
				GrabPass {
					Tags { "LightMode" = "Always" }
				}
				Pass {
					Tags { "LightMode" = "Always" }

					CGPROGRAM
					#pragma vertex vert
					#pragma fragment frag
					#pragma fragmentoption ARB_precision_hint_fastest
					#include "UnityCG.cginc"

					struct appdata_t {
						float4 vertex : POSITION;
						float2 texcoord: TEXCOORD0;
					};

					struct v2f {
						float4 vertex : POSITION;
						float4 uvgrab : TEXCOORD0;
					};

					v2f vert(appdata_t v) {
						v2f o;
						o.vertex = UnityObjectToClipPos(v.vertex);
						#if UNITY_UV_STARTS_AT_TOP
						float scale = -1.0;
						#else
						float scale = 1.0;
						#endif
						o.uvgrab.xy = (float2(o.vertex.x, o.vertex.y*scale) + o.vertex.w) * 0.5;
						o.uvgrab.zw = o.vertex.zw;
						return o;
					}

					sampler2D _GrabTexture;
					float4 _GrabTexture_TexelSize;
					float _Size;

					half4 frag(v2f i) : COLOR {
						//                  half4 col = tex2Dproj( _GrabTexture, UNITY_PROJ_COORD(i.uvgrab));
						//                  return col;

											half4 sum = half4(0,0,0,0);
											#define GRABPIXEL(weight,kernely) tex2Dproj( _GrabTexture, UNITY_PROJ_COORD(float4(i.uvgrab.x, i.uvgrab.y + _GrabTexture_TexelSize.y * kernely*_Size, i.uvgrab.z, i.uvgrab.w))) * weight
											//G(X) = (1/(sqrt(2*PI*deviation*deviation))) * exp(-(x*x / (2*deviation*deviation)))

											sum += GRABPIXEL(0.05, -4.0);
											sum += GRABPIXEL(0.09, -3.0);
											sum += GRABPIXEL(0.12, -2.0);
											sum += GRABPIXEL(0.15, -1.0);
											sum += GRABPIXEL(0.18,  0.0);
											sum += GRABPIXEL(0.15, +1.0);
											sum += GRABPIXEL(0.12, +2.0);
											sum += GRABPIXEL(0.09, +3.0);
											sum += GRABPIXEL(0.05, +4.0);

											return sum;
										}
										ENDCG
									}

											// Distortion
											GrabPass {
												Tags { "LightMode" = "Always" }
											}
											Pass {
												Tags { "LightMode" = "Always" }

												CGPROGRAM
												#pragma vertex vert
												#pragma fragment frag
												#pragma fragmentoption ARB_precision_hint_fastest
												#include "UnityCG.cginc"

												struct appdata_t {
													float4 vertex : POSITION;
													float2 texcoord: TEXCOORD0;
												};

												struct v2f {
													float4 vertex : POSITION;
													float4 uvgrab : TEXCOORD0;
													float2 uvbump : TEXCOORD1;
													float2 uvmain : TEXCOORD2;
												};

												float _BumpAmt;
												float4 _BumpMap_ST;
												float4 _MainTex_ST;

												v2f vert(appdata_t v) {
													v2f o;
													o.vertex = UnityObjectToClipPos(v.vertex);
													#if UNITY_UV_STARTS_AT_TOP
													float scale = -1.0;
													#else
													float scale = 1.0;
													#endif
													o.uvgrab.xy = (float2(o.vertex.x, o.vertex.y*scale) + o.vertex.w) * 0.5;
													o.uvgrab.zw = o.vertex.zw;
													o.uvbump = TRANSFORM_TEX(v.texcoord, _BumpMap);
													o.uvmain = TRANSFORM_TEX(v.texcoord, _MainTex);
													return o;
												}

												fixed4 _Color;
												sampler2D _GrabTexture;
												float4 _GrabTexture_TexelSize;
												sampler2D _BumpMap;
												sampler2D _MainTex;

												half4 frag(v2f i) : COLOR {
													// calculate perturbed coordinates
													half2 bump = UnpackNormal(tex2D(_BumpMap, i.uvbump)).rg; // we could optimize this by just reading the x  y without reconstructing the Z
													float2 offset = bump * _BumpAmt * _GrabTexture_TexelSize.xy;
													i.uvgrab.xy = offset * i.uvgrab.z + i.uvgrab.xy;

													half4 col = tex2Dproj(_GrabTexture, UNITY_PROJ_COORD(i.uvgrab));
													half4 tint = tex2D(_MainTex, i.uvmain) * _Color;

													return col * tint;
												}
												ENDCG
											}
										}
			}
}